Wow. Lots of questions.
1. DVD+R & DVD-R are two different standards. A player that only supports DVD+R will not play DVD-R, there is no universal industry standard for DVD recording.
2. Don't really know what this means, a scanner will make a digital copy of a document etc.
3. You can download .wma to .mp3 convertors from the web.
4. SD & MMC cards are physically similar; different but should be cross compatible; and should work in any devices (cameras, pocket PCs etc) which support SD. These are only 2 of many memory types for portable devices.
5. Don't have a PVR but I'd suspect that SP = Standard Play and LP = Long Play, so you can fit more on the PVR disk using LP but at less image quality.
6. ? You can port them to your PC. Are they good quality? Most have low resolution, fine for taking a picture if you've just been clamped but wont replace the digital camera just yet.
7. The AV on your TV should be input only not output, I doubt you could record from it.
I'm open to correction on any of the above.